The disclosure is directed to a method of treating humans suffering from V600 mutant melanoma that incorporates the detection of the presence or absence of at least one mutation in at least one NRAS protein and/or at least one MEK1 protein, or a gene encoding said protein, and subsequently initiating treatment, modifying treatment, or discontinuing treatment with a chemo-therapeutic agent selected from a BRaf inhibitor or other suitable agent based upon the presence or absence of said mutation.